It is often desirable and frequently necessary to sample or test a portion of tissue, particularly in the diagnosis and treatment of patients with cancerous tumors, pre-malignant conditions, and other diseases or disorders. Biopsy may be done by open, minimally-invasive, or percutaneous techniques. Open biopsy, which is an invasive surgical procedure using a scalpel and involving direct vision of the target area, removes the entire mass (excisional biopsy) or a part of the mass (incisional biopsy). Percutaneous biopsy, on the other hand, is usually done with a needle-like instrument through a relatively small incision, blindly or with the aid of an artificial imaging device, and may be either a fine needle aspiration (FNA) or a core biopsy. A minimally invasive procedure is performed by passing a sampling device through an endoscope or similar instrument such as a colonoscope or a ureteroscope.
Referring now to FIG. 1, a colonoscopy is shown wherein a physician 12, or endoscopist, performs a colonoscopy or other endoscopic procedure on a patient 14. During the procedure, the patient 14 is anesthetized while lying on a bed, cart, or stretcher 16. The patient 14 typically lies on his or her side, as shown. To perform a colonoscopy the physician 12 inserts a flexible tube 22 of a fiberoptic flexible colonoscope 24 through the rectum into the patient's colon. The flexible tube 22 usually contains a fiberoptic cable, an air line for inflating the colon, and a light for examining the mucosa therein. A communication cable 26 is coupled to medical equipment 28 supported by an equipment cart 30. The medical equipment 28 includes signal processing equipment and other control devices for supplying the camera signal to a video monitor 32. The cable 26 may also provide an avenue for passage of the air line for use in insufflation of the colon.
Also with reference to FIGS. 2-3, the doctor examines the entire length of the rectum B and colon C with the colonoscope 24. Special instruments such as elongated forceps 34 can be passed through a side port 36 in the colonoscope 24 to biopsy (sample) or remove any suspicious-looking areas such as polyps, if needed. For example, FIG. 3 shows a distal end effector or grabber 38 of the forceps 34 projecting from within the flexible tube 22.
As seen in FIGS. 4A and 4B, a distal end 40 of the colonoscope tube 22 includes a port 42 from which the distal grabber 38 of the forceps 34 emerges. A lens 44 provides the terminus of the fiberoptic cable, and a second open port 46 enables insufflation and expansion of the area. When the physician identifies a suspicious-looking area, such as the nodule N, he or she extends the distal grabber 38 and closes its jaws. The jaws are designed to resect and capture the nodule N, and the physician then can retract the grabber 38 proximally through the entire colonoscope tube 22.
Given that the colon is relatively long, the biopsy forceps 34 used in such procedures are thin flexible tubes (the length is typically between 2-3 m), as seen coiled in FIG. 5, which are advanced down and retracted back through the colonoscope tube 22. There are a number of different styles, with cup or teeth jaws and with or without a guide needle between the jaws, for example. One current supplier, Conmed of Utica, N.Y., offers a complete line of disposable biopsy forceps called the Precisor® Biopsy Forceps. Usually the process involves taking multiple samples, sometimes as many as 30-40 biopsies. The process of advancing the forceps 34, taking a sample, and then retracting the forceps is relatively time-consuming, and there is a need for a system that enables samples to be taken more quickly.